Sprinkle turkey breast with salt, pepper and paprika. Over medium heat, melt 1 tablespoon margarine in Dutch oven large enough to hold breast. Brown breast on both sides. Remove from pan. Heat remaining margarine in pan and sauté mushrooms for 1 minute. Sprinkle flour over mushrooms, stirring constantly. Remove from heat and stir in broth, sherry and crumbled rosemary. Return to medium high heat and cook until thickened.

Return turkey breast to pan, spoon sauce over and cover. Cook on low heat for 35 to 45 minutes or until juices run clear when pierced to the bone with a fork. Remove turkey to platter and slice. To serve, adjust seasonings in sauce to taste, and serve over turkey.